Fluid dispensing apparatus



July 15, 1969 P. CRIPPEN ET AL 3,455,487

FLUID DISPENSING APPARATUS Filed Sept. 13. 1967 "I I 22 2o PETER CRIPPENARTHUR JAMES EVANS AVI'ORNEYS United States Patent ()fice 3,455,487Patented July 15, 1969 3,455,487 FLUID DISPENSING APPARATUS PeterCrippen, Banstead, and Arthur James Evans, Stoke DAbernon, England,assignors, by mesne assignments, to The Distillers Company (CarbonDioxide) Limited, Reigate, England, a British company Filed Sept. 13,1967, Ser. No. 667,520 Claims priority, application Great Britain, Sept.16, 1966, 41,584/66 Int. Cl. B67d 5/06 US. Cl. 222-76 5 Claims ABSTRACTOF THE DISCLOSURE Apparatus for dispensing beer and similar liquidscomprising a diaphragm pump and various switches and valves to ensurethe delivery of measured quantities of the beer or liquid as required.

This invention relates to dispensing apparatus, more particularly toapparatus for the dispensing of liquids including carbonated liquids forexample beer.

It is already known to dispense liquids, by means which includepiston-operated or diaphragm pumps.

It is an object of the present invention to provide apparatus fordispensing liquids which provides various improvements over that alreadyknown.

Accordingly, the present invention provides apparatus for dispensing aliquid, hereinafter called beer, which comprises a diaphragm pump,fitted with (a) a beer supply pipe having a beer inlet nonreturn valveand (b) a beer dispensing pipe fitted with a nonreturn outlet valve, abeer dispensing valve and a dispensing control device,

(c) a pipe for supplying a fluid hereinafter referred to as air tooperate the diaphragm, fitted with an air control valve, a high speedexhaust valve and a flowoperated electromagnetic switch and electriccircuitry connecting the switches and valves in such a way that when thepump is full of beer and the dispensing control switch is operated, apredetermined volume of beer is dispensed.

The diaphragm pump used in the apparatus of this invention comprises twodished plates with a diaphragm between them. The beaded perimeter of thediaphragm is gripped by peripheral flanges in the dished plates but thecentral part is freely movable between the two dished plates. Thediaphragm provides an elfective seal for the joint between the plates attheir perimeters. It is preferably designed so that the part whichreceives beer is the upper part and is provided with a common inlet andoutlet port for the beer while the part which receives the air is thelower part. This is preferably also provided with a single port throughwhich theair can be introduced to exert pressure on the diaphragm andexpel the beer. This port can also be used for the discharge of the airfrom the pump after the beer discharge stroke. If desired, however, asecond port could be provided for this purpose and this could also becontrolled by means of, for instance, a solenoid valve. It has beenfound that if the neck of the common inlet and outlet port is widened sothat its diameter is greater than that of the beer dispensing pipe abetter response is obtained at the end of the dispensing cycle, when thepre-determined quantity of beer has been displaced from the pump. Toassist this quick shut off from the constant velocity condition thatexists during the beer discharge stroke the diaphragm is provided with apad or thickened portion at that part of it which corresponds with thewidened neck. This is a preferred feature of the invention. If desired avolumetric adjustment device can be incorporated in the pump, forexample secured to the bottom diaphragm plate or the underside of thediaphragm. This device may be a disc perforated with a number ofconcentric rings and having a central hole. This stroke of the diaphragmthen depends on the number of rings in the disc and so can be varied asdesired.

The 'material used for the construction of the dished plates may be offerrous or non-ferrous type, for example aluminum. The surfaces incontact with the beer or liquid being dispensed are suitably coated withan epoxy resin or nickel tin plating. Plastic diaphragm plates may alsobe used.

The beer supply pipe preferably has a fairly large bore for example /8inch internal diameter to permit rapid filling of the pump after eachcycle. It can be fitted if desired with a branch connection for cleaningpurposes.

The beer dispensing pipe, however, is preferably ot a smaller bore forexample inch internal diameter. This provides a high rate of flowthrough the pipe which ensures self-cleansing of the pipe and theavoidance of the collection of sediment in the apparatus. The beerdispensing valve and dispensing control device is conveniently locatedat the bar or other dispensing point. They can be manual, electric orpneumatic. The dispensing control device is preferably a press buttonswitch which on pressing closes an electric circuit.

The flow-operated switch in the air supply pipe may be any device whichwill actuate an electrical circuit when the rate of flow of air throughit reaches a certain value. A preferred device comprises a valve body ofnon-magnetic material through which the air can pass, at least onemagnetic reed switch mounted adjacent to the valve body and a non-returnvalve with a magnetic core which actuates the switch when the valve isadjacent to it. The valve is, however, responsive to the flow of airthrough the pipe and when it is thereby caused to move away from theswitch, the circuit is broken.

The high speed exhaust valve may be incorporated in the air controlvalve for instance as a three-way solenoidoperated valve which when opensupplies air to the pump, but when closed cuts off the air and providesa vent to the atmosphere for the air in the pump. It is preferred,however, to have a high speed exhaust valve close to the air inlet ofthe pump in order to remove air from the pump chamber in the quickestpossible time, thereby ensuring rapid refilling of the pump with beer. Aconvenient high speed exhaust valve depends on pressure differences inthe pipe and only operates when such a difierence exists, i.e. in theapparatus of the invention when the air flow is cut off.

The circuitry connects the switches and valves in such a way that whenthe dispensing control device is operated the valves in the air supplypipe and the beer dispensing pipe are opened, whereupon the flow of airthrough the electromagnetic switch in the air supply pipe into the pumpforces the diaphragm across the chamber and so displaces beer throughthe outlet port and the beer dispensing valve which has beensimultaneously opened. When the pump chamber is empty, air ceases toflow, so that the switch in the air supply pipe opens the circuit andthe valves in the air supply pipe and the beer dispensing pipe areclosed and the air vent is opened so that th air in the pump is ventedto the atmosphere under the pressure of the beer which flows into thepump from the beer container and so fills the pump with beer ready foranother cycle.

The beer is maintained in a reservoir at a sufficient pressure to causeit to enter and fill the dispensing chamher when the vent is open. Thereservoir can be refrigerated if desired.

The invention further comprises means whereby the sequence of operationscausing beer to be dispensed can only be commenced when the dispensing;chamber of the pump is full of beer. This is achieved by placing asecond switch of the type hereinbefore described before the air escapevent. This switch is so arranged as to prevent completion of theelectrical circuit initiating the dispensing sequence of operationswhilst airis passing through the switch. As soon as the air ceases toflow, that is to say when the dispensing chamber is full of beer, theswitch returns to its rest position and permits the electrical circuitto be completed.

The drawing accompanying the provisional specification illustrates oneembodiment of the invention.

FIGURE 1 is a representation of apparatus suitable for dispensing beer.

FIGURE 2 gives the electrical circuit of the apparatus.

In FIGURE 1 is shown a diaphragm pump 1 consisting of two dished piecesof metal 2 and 3 fitted together to form a dispensing chamber 4 acrosswhich is situated a flexible diaphragm 5 which is provided with a pad orthickened portion 25 and which is provided with beer port 6 and an airport 7. Air is fed to the dispensing chamber 4 from a pressurised store8 by means of the pipe 9 in which is situated a solenoid valve 10 and aflow-operated switch 11. Built into solenoid valve 10 is an escape pipe12 which passes through a second flow-operated switch 13 to vent 14.Solenoid valve 10 either permits air to flow from the pressurised source8 and closes escape pipe 12 or shuts off the air supply and opens theescape pipe.

Beer is stored in a reservoir 15 at 35 p.s.i., pressure applied by forinstance carbon dioxide through line 15a. It is fed to the dispensingchamber 4 by means of pipe 16 which passes through a non-return valve 17to the beer port 6.

Beer is expelled from the dispensing chamber 4 through port 6, through anon-return valve 18, and by means of pipe 19 to a solenoid valve 20 andfinally to a dispensing point 21.

In FIGURE 2 is shown the electrical circuit for the apparatus justdescribed. A push-button switch 22, a relay 23 and an optionaldispensing counter 24 are shown in addition to the features alreadydescribed.

Before a dispensing-cycle is initiated the dispensing chamber 4 is fullof beer; that is to say the flexible diaphragm 5 is in the positionshown in FIGURE 1, the solenoid valves 10 and 20 are closed, switch 11is open and switch 13 is closed. The dispensing cycle is initiated bydepressing push button switch 22 which energizes relay 23 which in turnenergizes and opens solenoid valves 10 and 20. The opening of solenoidvalve 10 permits air to flow through switch 11 thereby closing saidswitch and maintaining the system in operation. The flow of air underpressure through port 7 acts on the reverse side of the diaphragm 5forcing the contents of the dispensing chamber through port 6, throughnonreturn valve 18, through solenoid valve 20 to the dispensing point21. As soon as the diaphragm completes its stroke no further air passesinto the dispensing chamber and flow of air through switch 11 ceases,causing it to revert back to its open position. Relay 23 and solenoidvalves 10 and 20 are de-energised which has the effect of closing saidvalves, the closing valve 10 causing escape pipe 12 to be opened. Air isthen forced through vent 14 via pipes 9 and 12 from the dispensingchamber 4 under the pressure of beer acting on the other side of thediaphragm. The venting of air through switch 13 opens the switch andprevents initiation of the dispensing cycle until the flow of air ceaseswhen the dispensing chamber is full of beer, whereupon the switch 13reverts back to its closed position. The apparatus is then ready for afurther dispensing cycle. Besides the dispense cycle counter 24 acontinuous cycling device for cleaning purposes could also be includedin the system if desired.

We claim:

1. Apparatus for dispensing a liquid which comprises a diaphragm pump,fitted with (a) a liquid supply pipe having a liquid inlet nonreturnvalve,

(b) a liquid dispensing pipe fitted with a non-return outlet valve, anelectrically operated liquid dispensing valve and a dispensing controlswitch,

(0) a pipe for supplying a fluid to operate the diaphragm, fitted withan electrically operated fluid control valve and a fluid flow-operatedelectromagnetic switch and electric circuitry connecting the switchesand valves, whereby when the pump is full of liquid and the dispensingcontrol switch is operated, the circuit is closed, causing the fluidsupply valve and the liquid dispensing valve to open and the fluidexhaust valve to close, whereupon fluid flows into the pump and drivesliquid out until the pump is empty of liquid, the fluid ceases to flowso that the electromagnetic switch opens the circuit which shuts off thefluid supply and closes the liquid dispensing valve, but the fluidexhaust valve opens so that liquid flows into the pump under pressurefrom the liquid container until the pump is full again and ready for afurther dispensing cycle.

2'. Apparatus as claimed in claim 1 wherein a fluid exhaust pipe isconnected into the fluid supply pipe and an electro-magnetic fluidflow-operated switch is fitted in the fluid exhaust pipe, the switch iselectrically connected into the circuitry so that as long as fluid isflowing, the switch is open and liquid cannot be dispensed.

3. Apparatus as claimed in claim 1 wherein the diaphragm pump has acommon inlet and outlet valve for the liquid.

4. Apparatus as claimed in claim 1 wherein the outlet port of the pumpis of greater diameter than the liquid dispensing pipe and the diaphragmhas a pad or thickened portion at that part of it which corresponds withthe port.

5. Apparatus as claimed in claim 1 wherein the flowoperated electricalswitch is a magnetic reed switch.

References Cited UNITED STATES PATENTS 2,388,662 11/1945 Anderson et al.222-334 X 3,220,608 11/ 1965 Porter 222334 X 3,227,314 1/1966 Porter etal 222334 X ROBERT B. REEVES, Primary Examiner H. S. LANE, AssistantExaminer US. Cl. X.R. 222334

